My Land Rover makes 38 hp at the wheels, and it does okay. There are some hills that it can't take at speed and it doesn't want to spend any time above 60 mph, but a big part of that is the fact that it's running a 1950's 4x4 drivetrain with the aerodynamics of a garage. So yeah, I can see that 30 hp would satisfy your needs MOST of the time including around town.
oldopelguy wrote:D2W wrote: 5-30hp is all most people use? To me this begs the question why isn't one of the automakers building this car? A small commuter with 30 hp that gets 80 to 100 mpg. Nobody here would want it, but I know there is a lot of people out there that would.The Mirage is close, over 50mpg if you pay attention, and everyone here calls it the worst car ever. Clearly no one actually wants what they say they want.
It can't do the quarter in 11 seconds or tow 18,000 pounds.
D2W wrote:alfadriver wrote:5-30hp is all most people use? To me this begs the question why isn't one of the automakers building this car? A small commuter with 30 hp that gets 80 to 100 mpg. Nobody here would want it, but I know there is a lot of people out there that would.tuna55 wrote: Alfadriver: Has there ever been a real study of an understressed low RPM, low power large displacement as compared to a high strung turbo small displacement engine within your walls? We model performance on our stuff like crazy. I can only imagine that you guys do too. My instinct tells me that they would be very close to each other in most real world reasonable scenarios (no 50CC turbo 2s compared with 9 liter V10s).The hardest of the hard part isn't making a lot of power, it's making very little efficiently. In terms of power and torque, many of our small displacement turbos are better than their "equal" normally aspirated- mostly because boost means low end torque that is nice to drive. But most of use normally use 5-30 hp on a normal day. That's it. This board will generally use more for honing, but if you just are doing traffic- 5-30 is all you really use. And small engines do that better. So the trick is making a small engine act like a big one (boosting) or a big engine act like a small one (turning cylinders totally off via valvetrain). The discussion you speak of has been going on for years- trying to find the sweetspot of weight to displacement. Sometimes they do it pretty well, sometimes not.
Marketing.
35 years ago, most cars had 0-60 times in the ~10-12 second range. Now they can do that in 6-8 seconds. Why? Because.
My CRX HF had all of 65 hp. And I never had a problem with speed and power keeping up.
Next time you get on a freeway, pay attention to those around you- they are still accelerating at 80's times, and not using the power of the engine.
BTW, I'm not exaggerating in terms of the power used- most people accelerate so gently getting on the freeway, they don't use more than 30 hp. Which allows early shifts to low speeds/high torques.
Truck can add 10-20 hp in their days.
Heck, we have HUGE tow abilities, and people still drive trucks empty and one passenger.
Between the fact that people buy potential over what they need, and increased safety requirements- that's why fuel economy has crept up so very slowly (as a fleet).
I always find it funny to enter a freeway with that BMW guy who just got the car for image. They crawl so slowly that I can keep up really easy with my 1.6l Fiesta.
That's a good point, the only vehicle I drive that I frequently use all of its 300+ horses in day to day driving is my big, fully loaded box van, and then usually only getting on the interstate on our stupidly short, sometimes uphill ramps.
In reply to Rufledt:
And that's more like the big tractor trailers who commonly use their 600hp motors. Some engine requirements are totally needed for work, some are there to sell more cars.
1988RedT2 wrote:D2W wrote:I haven't checked the latest acceleration numbers on modern hybrids, but it seems to me that someone would build a car that used a small, efficient ICE to provide that 30 HP, and then kept a big honking electric motor on stand-by that could roast the tires if the driver so mandated.alfadriver wrote:5-30hp is all most people use? To me this begs the question why isn't one of the automakers building this car? A small commuter with 30 hp that gets 80 to 100 mpg. Nobody here would want it, but I know there is a lot of people out there that would.tuna55 wrote: Alfadriver: Has there ever been a real study of an understressed low RPM, low power large displacement as compared to a high strung turbo small displacement engine within your walls? We model performance on our stuff like crazy. I can only imagine that you guys do too. My instinct tells me that they would be very close to each other in most real world reasonable scenarios (no 50CC turbo 2s compared with 9 liter V10s).The hardest of the hard part isn't making a lot of power, it's making very little efficiently. In terms of power and torque, many of our small displacement turbos are better than their "equal" normally aspirated- mostly because boost means low end torque that is nice to drive. But most of use normally use 5-30 hp on a normal day. That's it. This board will generally use more for honing, but if you just are doing traffic- 5-30 is all you really use. And small engines do that better. So the trick is making a small engine act like a big one (boosting) or a big engine act like a small one (turning cylinders totally off via valvetrain). The discussion you speak of has been going on for years- trying to find the sweetspot of weight to displacement. Sometimes they do it pretty well, sometimes not.
You kinda just described the first hybrid. The Honda Insight. It was primarily driven off of it's small 3 cylinder engine, but had an electric "boost" for acceleration
In reply to oldopelguy:
That's because the entire car is a pile of E36 M3. But because it gets 50mpg.
All I can tell you is having sampled both is this...
Put two identical cars side by side. One has a small boosted motor, one has displacement. Both make identical hp and tq numbers. I can tell you which one I'm taking. Displacement every day of the week and twice on Sunday.
I don't hate small boosters, but definitely prefer big 'uns. Hmmm...kinda like another preference I have... 
In reply to Klayfish:
Odd. I much prefer my turbo 1.9 to a larger engine of the same power output. It's efficient when it needs to be and it scoots when it needs to. Plus it doesn't need to rev nearly as high. I don't think the engine ever exceeds 3000rpm. It's like driving a turbodiesel except with cheap fuel, and it doesn't smell like baby barf or sound like it is actively trying to disassemble itself. And it has throttle response instead of molasses-like "response". So more or less it is like driving a turbodiesel without all of the things that make turbodiesels dreadful.
It is atrocious for a sporting engine, but I don't want or need a sporting engine to get me from A to B.
Klayfish wrote: All I can tell you is having sampled both is this... Put two identical cars side by side. One has a small boosted motor, one has displacement. Both make identical hp and tq numbers. I can tell you which one I'm taking. Displacement every day of the week and twice on Sunday. I don't hate small boosters, but definitely prefer big 'uns. Hmmm...kinda like another preference I have...
Back in 2010, I thought that truck buyers thought exactly like you do. Moreso that truck buyers would never want a turbo V6 to replace a V8.
Now we are seeing that there's a really big chunk of truck buyers who are getting the turbo V6s instead of V8s.
I had to change my mind about buyers.
Certainly, there are buyers like you. But not nearly as many as I thought.
Keith Tanner wrote: My Land Rover makes 38 hp at the wheels, and it does okay. There are some hills that it can't take at speed and it doesn't want to spend any time above 60 mph, but a big part of that is the fact that it's running a 1950's 4x4 drivetrain with the aerodynamics of a garage. So yeah, I can see that 30 hp would satisfy your needs MOST of the time including around town.
Same sort of thing is the MKI Rabbit diesel, 48hp and a 4spd. I usually got well over 40mpg; usually over 50 and it wasn't so slow as to be dangerous; you do choose your roads. 
. I also had a pickup, a Boxster, an AMG W126 and a civic.
Now "we" want one vehicle that will do all the things and the needs of different people make different bogies for the car companies to hit.
mad_machine wrote: You kinda just described the first hybrid. The Honda Insight. It was primarily driven off of it's small 3 cylinder engine, but had an electric "boost" for acceleration
True enough, but the Insight was never known for rapid acceleration. The emphasis was on fuel economy. I'm saying that there may be a market for a car with the wheezy little 3 cylinder engine, but also a big torque-y electric motor for a significantly greater "boost." Same great fuel economy for the 90% of the time when you're just tooling down the road, but with an invigorating rush of (electric) power when you want it.
In reply to 1988RedT2:
One of my customers has a de-electriced Insight. It still functions perfectly adequately with nothing but the 1.2l engine.
Nothing to add other than I'm enjoying this thread. Thanks everyone for sharing your insight.
Jeff wrote: Nothing to add other than I'm enjoying this thread. Thanks everyone for sharing your insight.
pun intended? 
Would another reason for this be that it is much easier to muck with a boosted motor to make crazy hp versus a motor that is NA?
Knurled wrote: In reply to 1988RedT2: One of my customers has a de-electriced Insight. It still functions perfectly adequately with nothing but the 1.2l engine.
The electric assist is tiny on that car. 25 ft lbs and 10kw max if the internet is to be believed.
Knurled wrote: In reply to Klayfish: Odd. I much prefer my turbo 1.9 to a larger engine of the same power output. It's efficient when it needs to be and it scoots when it needs to. Plus it doesn't need to rev nearly as high. I don't think the engine ever exceeds 3000rpm. It's like driving a turbodiesel except with cheap fuel, and it doesn't smell like baby barf or sound like it is actively trying to disassemble itself. And it has throttle response instead of molasses-like "response". So more or less it is like driving a turbodiesel without all of the things that make turbodiesels dreadful. It is atrocious for a sporting engine, but I don't want or need a sporting engine to get me from A to B.
I don't hate small boosted engines. I've sampled many of them, and after doing so wound up buying a FoST. There was a lot of stuff I liked about it. When it was on boost, it was wicked. Incredible low end torque, it pulled from under 2k rpm. Respectable fuel economy. At the same time, the boost was a bit unpredictable. Sometimes it would come gushing on, other times the engine fell flat on its' face. I know it's a curable problem, but heat soak seemed to be noticeable. Late in my 90+ minute commute, some of which was stop and go, the boost didn't seem to be what it was early on. A n/a larger displacement engine is more predictable in those ways.
Also, no matter how good an tubro 4 is, it can't make the sounds a displacement V8 (or even V6) can make.
Plus, my personal history is lots of n/a displacement...Viper, FFR Cobra, 'Vette, GTO, Mustangs, etc... I'm not dismissing small turbo motors, I'd give another one a try, but I like larger engines. Or, when they fall into my price range, I'm all in for a zero displacement engine. I owned a Leaf, which wasn't designed for performance, and the off the line torque always made me giggle. I'd love to have a Tesla.
In reply to Klayfish:
Sounds like Ford needed to spend more effort in thermal management 
Of course the sample I'm judging by has an intercooler larger than the radiator, thin and lots of frontal surface area, so "heat soak" just doesn't happen.
I understand where you're coming from. Heck, my first car had a 429 and I loved it. And I staunchly believe that sporting engines need to be naturally aspirated if rules don't require a turbo. Maybe I'm just getting old, I don't want to live with a sporting car every day anymore.
Hope this means a comeback for 6 cyl in mid sized sedans.
Couldnt stand the high boost little 4 cyl and all the gear hunting it would make the auto trans do.
i think some it has to do with all these new 7 or 8 or 9 speed transmissions as well ( i dont know how many speeds they are up to now). When you get into your high gear and it drops to a low rpm then your displacement doesnt make much of a difference, but when you need to accelerate from high gear, a small turbo, less torquey engine will have to drop 3, maybe 4 gears to get going. Where a bigger displacement engine will only drop 1-2 gears and use its low end torque to pull i through.
that i my theory anyways.
In reply to edizzle89:
Unused displacement matters a lot... That, and I've seen very few gas engines that have really good combustion below 1300rpm, and most that limit is closer to 1500- so going lower and lower in speed has some seriously diminishing returns via combustion efficiency.
But that under used displacement issue is why you see variable displacement engines.
I enjoy my 1.6 supercharged MINI. Feels like a bigger engine, reasonable, but not great economy.The one thing I'm not fond of is the requirement for higher octane (93) and the associated cost.I get the same cost per mile as a 24 mpg vehicle on 87 octane. Do modern turbo cars, like the Fiesta need high test?
In reply to DeadSkunk:
Depends on which version. Many mainstream cars are set up to run regular. MINI is BMW, so perhaps they think the customers can deal with it.
BUT- there is some movement in the industry to change the whole fuel supply to premium. That, and reducing the huge variety of regional blends, will lower the cost of gas (relative to the barrel cost).
I haven't checked the latest acceleration numbers on modern hybrids, but it seems to me that someone would build a car that used a small, efficient ICE to provide that 30 HP, and then kept a big honking electric motor on stand-by that could roast the tires if the driver so mandated.
That is getting closer and closer to feasible as the batteries improve, but the limiting factor so far is customer expectations, i believe. Compare the Volt to an older Plugin Prius, for example. The Volt is big enough in electric motor, battery, and ICE generator that it basically maintains its full performance envelope even after it's exhausted its EV range and is being sustained (if not propelled) by the ICE. The Prius on the other hand, never has its full performance available unless the ICE is running.
A hybrid with a very powerful motor and a small ICE generator would suffer a huge performance dropoff when it transitioned from EV range to 'range-extended' mode unless it was designed to leave a huge buffer zone in the battery state-of-charge.
I was actually excited that Mazda was toying with your general idea when they built a Mazda2 hybrid with a small rotary ICE generator. I assume i would love the hell out of that car if i owned it.
You kinda just described the first hybrid. The Honda Insight. It was primarily driven off of it's small 3 cylinder engine, but had an electric "boost" for acceleration
The 1g Insight was only built to be as quick as an equivalent 1.5L car. It does that, but those were not heady times for 1.5L cars. I owned an Insight and a CRX HF at the same time and i can say the Insight accelerated the same and had 15+mph more top speed while having tons more 'content' at the exact same weight. The progress was undeniable.
One of my customers has a de-electriced Insight. It still functions perfectly adequately with nothing but the 1.2l engine.
I have lived this life and it's not 'perfectly acceptable'. I would say most people would characterize it as 'punishing'. But, it's not really the ICE's fault. It's the ludicrously tall gearing. I suspect that a 1.0L Insight with normal Civic gearing would actually drive pretty well.
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